Investigation of the IGBT’s and Diode’s Ruggedness Under Short-Circuit Type III Conditions Well Beyond the SOA

This paper showcases the study of the ruggedness limit of an IGBT and a freewheeling diode (FWD) under short-circuit type III (SC-III) conditions. SC-III measurements at low parasitic inductance (Lpar) with gate emitter voltage (VGE) clamping show approximately the same destructive boundary limit as for SC-I, even though the IGBT undergoes harsher conditions in an SC-III event compared to an SC-I event. At low Lpar, only IGBT failure were observed during the SC-III event. However, SC-III critical-current limit reduces at high Lpar, at which the device leaves the specified IC-VCE parameters space. Furthermore, increased load currents (Iload) and temperatures can be critical for the robustness of the corresponding FWD. At higher DC-link voltage and load currents, the diode fails due to overvoltage at SC-III turn-off and strong dynamic avalanche at 300 K and 400 K, respectively.